Fitting for preformed shower pans

ABSTRACT

A fitting for use with preformed shower pans, which facilitates installation of the drain pipe in the fitting and removal of the drain pipe if repairs are needed at a time after installation. The fitting has a tubular portion closely received and passing through a drain hole in the shower pan, and has a flange at the top for resting on the upper surface of the shower pan. Two tapered inside threads are formed on the fitting, one extending into the lower end and the other into the upper end, for receiving a drain pipe and test standup, respectively. A thread is formed on the outside of the lower fitting portion for receiving a nut that holds the fitting securely to the shower pan. If the drain pipe must be removed, this can be accomplished without damaging the outside threads by one workman stationed below the shower pan, who can grasp the nut with one wrench and the drain pipe with another wrench and turn them in opposite directions, any turning of the nut merely further tightening it so that the drain pipe will soon begin turning to become loosened.

United States Patent 1 [111 3,744,065 [451 July 10, 1973 Yavitch FITTING FOR PREFORMED SHOWER PANS [76] Inventor: Morris Mich, 1008 Benedict Canyon Drive, Beverly Hills, Calif. 90210 [22] Filed: June 1, 1971 21 Appl.No.: 148,635

[52] US. Cl. 4/146 [51] Int. Cl A4711 3/22 [58] Field of Search 4/145, 146, 191,

Primary Examiner-Henry l(. Artis Attorney-Lindenberg, Freilich & Wasserman [5 7] ABSTRACT A fitting for use with preformed shower pans, which facilitates installation of the drain pipe in the fitting and removal of the drain pipeif repairs are needed at a time after installation. The fitting has a tubular portion closely received and passing through a drain hole in the shower pan, and has a flange at the top for resting on the upper surface of the shower pan. Two tapered inside threads are formed on the fitting, one extending into the lower end and the other into the upper end, for receiving a drain pipe and test standup, respectively. A thread is formed on the outside of the lower fitting portion for receiving a nut that holds the fitting securely to the shower pan. If the drain pipe must be removed, this can be accomplished without damaging the outside threads by one workman stationed below the shower pan, who can grasp the nut with one wrench and the drain pipe with another wrench and turn them in opposite directions, any turning of the nut merely further tightening it so that the drain pipe will soon begin turning to become loosened.

4 Claims, 4 Drawing Figures FITTING FOR PREFORMED SHOWER PANS BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to plumbing fittings designed for use with preformed shower pans.

2. Description of the Prior Art One method which has been previously used to form shower pans involved cutting a hole in the floor of a house and spreading tar paper on the flooring. A drain nipple with a large flange was placed beneath the tar paper, and a clamp member was placed above the tar paper and fastened to the nipple by several screws passing through the tar paper and engaged with threaded holes in the flange of the nipple. The clamp and tar paper were then fixed in position and protected by concrete poured over them. A drain pipe could be threadably engaged with the nipple for secure installation. If the drain pipe had to be removed at some later date, this could be accomplished by a single workman stationed beneath the pan who tightly grasped the drain pipe with a large pipe wrench and turned it. The large flange on the nipple, which was held by bolts embedded in concrete, prevented turning of the nipple even though a very large torque might have to be applied to loosen the drain pipe.

In many modern installations, preformed shower pans are utilized which may be constructed of a thick, tough plastic and which do not require tar paper sheeting, clamps, or concrete pouring. Such a pan has a central hole and is designed to receive a drain fitting. The drain fitting has a. tubular portion slightly smaller than the hole for close fitting therein and a flange for resting on the upper surface portion of the shower pan immediately around the drain hole. In many installations, drain pipes are installed by locating their upper ends within the fitting and employing a plaster or other compound to seal them into place. If the drain pipe must be removed for repairs some time after installation, considerable work is required in removing the hardened plaster or other caulking compound and in later reinstallation. While threadtype coupling of the drain pipe to the drain fitting can be used, this sometimes can lead to difficulties during installation or removal when the pipe has to be turned. Difficulties can arise because the drain fitting may not be securely held against turning, as was the case in previous installations wherein the drain nipple or fitting had a large flange wich was held by fasteners set in concrete.

SUMMARY OF THE INVENTION In accordance with one embodiment of the invention, a drain fitting is provided for use with preformed shower pans of a type which can provide sole support for the fitting, the fitting being constructed to facilitate removal of the drain pipe for repair and to facilitate its reinstallation. The fitting has a tubular or pipe portion that can be projected through a drain hole formed in the pan, and also has a flange for resting on top of the pan. An outside thread is formed along the lower portion of the tubular body for receiving a nut which can be tightened against the lower surface of the pan to hold the fitting securely in place. An internal tapered,- or pipe thread is formed at a lower portion of the tubular body for threadably receiving a drain pipe, and another internal pipe thread is formed at the upper region of the body for threadably receiving a test pipe that can seal the drain hole region during testing of the pan installation for leakage. I

The fitting not only provides secure holding of a drain pipe but also facilitates its removal and installation, particularly if repairs must be made at a time long after installation when removal may be very difficult. A single workman who is stationed below the pan can remove a drain pipe by grasping the drain pipe with one wrench and the nut that is screwed on the outside of the fitting with another wrench, and turning them in opposite directions. If the drain pipe threads are frozen to the fitting threads, so that the fitting turns when the drain pipe is turned, this will merely cause further tightening of the nut, until itis so tight that it prevents turning of the fitting and the drain pipe starts to loosen from it. Any scoring of the drain pipe by a wrench generally does not affect its functioning, while the nut can be securely grasped and any scoring of its outer surface also does not affect its functioning. There is no need to apply a wrench directly to the outside of the fitting where the threads are located, which could cause damage to the thread that would be highly detrimental if the nut later has to be removed. The internal threads at the upper portion of the fitting can receive a test pipe, and also can be used to facilitate tight installation of the drain pipe where a second workman is available. The second workman can threadably install a test pipe or the like on the fitting and hold it against turning, to allow a workman below the pan to fully tighten the drain pipe and/or the nut.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a preformed shower pan with a drain installation therein;

FIG. 2 is a perspective exploded view of a drain fitting and other members used therewith for installation on the pan of FIG. 1;

FIG. 3 is a sectional view of the pan of FIG. 1, shown with the apparatus of FIG. 2 fully installed thereon; and

FIG. 4 is a partial perspective view of a drain and preformed shower pan, wherein the drain fitting has a nut circular flange received in a corresponding recess of the pan to facilitate installation.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1-3 illustrate a preformed pan 10 with a drain assembly 12 installed thereon. The preformed pan may be constructed of reinforced plastic of sufficient thickness to provide high structural strength. The pan is formed with a drain hole 14 at its center for closely receiving a drain fitting, and with a recess 16 in the upper surface of the pan around the drain hole for receiving a flange on the fitting. The drain fitting 18 has a tubular or pipe portion 20 designed to be closely received in the shower pan hole, and a flange 22 at its upper end which is designed to be received in the recess 16 of the pan. The tubular body 20 of the fitting has an external thread 24 on the outside and extending along its lower portion, for threadably receiving a tightening nut 26. The tubular portion of the fitting also has two tapered, or pipe threads on its inner surface, one of the threads 28 formed at its lower portion for threadably receiving a drain pipe 30 and the other thread 32 being formed at its upper portion for threadably receiving a test stand-up 34 that is utilized to test a shower pan installation for leakage.

A workman can install the fitting assembly 12 by first lowering the fitting 18 through the drain hole of the shower pan and then positioning himself beneath the pan. The workman can then install an elastic seal washer 36, protective washer 33, and the tightening nut 26 over the lower end of the fitting and screw the nut tightly against the lower surface of the pan, to provide a secure and water-proof installation of the fitting on the pan. He can then screw the drain pipe 30 into the pipe threads 28 of the fitting. In many cases, the shower pan installation is then tested for leakage by plugging the inside of the fitting and filling the shower pan with water to see if any water leaks out. The plugging of the fitting can be accomplished be screwing the test standup 34 into the thread 32, and after testing is completed the test stand-up can be removed by unscrewing it. Finally, a grill 40 is laid in a groove 42 at the top of the fitting.

Plumbing malfunctions sometimes occur which require removal of the drain pipe 30 from the fitting 18. The drain pipe 30 may be frozen by corrosion or otherwise difficult to remove from the fitting 18, particularly if a long period of usage has passed since the installation. A workman can securely grasp the drain pipe 30 with a large pipe wrench to rotate it for removal, but this may result in rotation of the fitting 18. The workman could apply a second large wrench to the outside of the fitting on the threads 24, but this could damage the threads and prevent later removal of the nut 26. A workman can remove a frozen drain pipe 30 by applying another wrench to the tightening nut 26 to prevent its counter rotation. If the fitting 18 should rotate when the pipe 30 is turned, this will result in further tightening of the nut 26, until it is so tight that it will not turn relative to the fitting and the drain pipe 30 begins to loosen from the fitting and then can be easily removed. If it is found that the nut 26 has also become frozen in place, and it is desired to remove it, this can be accomplished by installing the drain pipe 30 or another similar pipe, to hold the fitting from turning while the nut 26 is loosened. The tapered internal pipe thread 28 prevents screwing in of the drain pipe 30 past a particular depth even if the threads were cut to a further depth. Such a newly installed pipe used for holding the fitting during loosening of the tightening nut 26 can be more easily removed because it will not be frozen into place, such freezing often being due to corrosion that requires an extended period to occur. Thus, removal of the drain pipe 30 and/or the nut 26 can be accomplished even if they are initially frozen in place, by a single workman stationed beneath the shower pan.

The design of the fitting 18 also facilitates initial installation of the drain pipe 30 and nut 26, where another workman is available that can be stationed above the shower pan. In order to prevent turning of the fitting 18, the second workman can thread the stand-up pipe 34 into threads 32 and hold the pipe 34 against rotation. This permits a workman below the pan to turn the drain pipe 30 and nut 26 in directions to install them without causing rotation of the drain fitting 18. In many cases, there is no need for an additional workman to secure the fitting 18 against rotation during installation of the drain pipe or nut. However, if the threads on the drain pipe 30 or fitting 18 have been damaged by rough handling, they may be difficult to install and help may be useful in preventing fitting rotation during such installation. Of course, in the above discussion it is assumed that all threads are of the same hand, and in practice generally all of the threads are right-handed. The internal thread 28 on the'drain fitting is shown tapered, as this provides a very secure attachment to a taper-threaded drain pipe 30. However, it is possible to use straight, or untapered internal threads on the drain fitting 18 in conjunction with tapered, or pipe threads on the drain pipe 30 and/or the test stand-up 34. When a taper-threaded drain pipe is screwed into a straightthreaded fitting, it will become tight, even though only the last few threads on the drain pipe are tightly held. Such straight internal threading of the fitting can be employed to lower the cost of manufacture, inasmuch as threading then can be accomplished with a single threading tap instead of requiring two threading taps entering from opposite ends.

FIG. 4 illustrates a shower pan 50 and drain fitting 52 which are constructed in accordance with another embodiment of the invention, and which are also designed to facilitate installation and removal of the fitting and of a drain pipe. The preformed shower pan 50 has a round drain hole 54 designed to closely receive a tubular portion 56 of the fitting, and a square recess 58 around the drain hole for receiving a square flange 60 on the fitting. The fitting has threads 62 on the outside of its lower portion for receiving a tightening nut and has tapered, or pipe threads 64 and 66 extending downwardly and upwardly, respectively, into the inside of the fitting for receiving a stand-up and drain pipe. When the fitting 62 has been placed in position on the pan 50, the square flange 60 prevents rotation of the fitting to facilitate screwing on and off of the nut and pipes. Not only can most installations and removals of pipes and nuts on the fitting be accomplished by a single workman at one station (usually below the pan except during installation of the test stand-up), but installation is easier because the workman generally has to utilize only a single wrench. The flange 60 does not have to be square, but can be of almost any noncircular shape so long as the recess 58 in the pan is formed to mate with it so as to prevent rotation of the flange. However, a square flange is generally desirable because it is relatively uncomplicated in shape, can be installed at any one of four rotational positions, and provides a high degree of resistance to rotation in a fitting of minimum size. In most cases, the shower pan 50 is of rectangular shape, and the sides of the square flange-receiving depression 58 should be formed parallel with the edges 68 of the pan so as to provide a symmetrical appearance.

Thus, the invention provides drain fittings for preformed shower pans of the type which have a drain hole for closely receiving a fitting. The fittings are formed to facilitate installation of the drain pipe and fastening nut and particularly to facilitate removal of the drain pipe at a time long after initial installation when the pipe may be frozen in place due to corrosion or the like.

Although particular embodiments of the invention have been described and illustrated herein, it is recognized that modifications and variations may readily occur to those skilled in the art and, consequently, it is intended that the claims be interpreted to cover such modifications and equivalents.

What is claimed is:

1. A drain fitting for use on a preformed shower pan that has a drain hole of predetermined diameter comprising:

a fitting body having a tubular portion for passage through said drain hole, a flange at a first end of said tubular portion for lying on the pan region surrounding said drain hole, a first thread formed on a fitting having a tubular portion for extending through said hole, said tubular portion having upper and lower end portions and having a noncircular flange received in said depression to prethe outside of said tubular portion for threadably 5 vent turning of said fitting, said tubular portion also receiving a nut to hold said fitting body so the having an external thread on its lower end portion; flange is held down tightly to the pan region surand rounding the drain hole, and a second thread a nut threadably engaged with said external thread formed on the inside of said tubular portion to reand tightened thereon to hold the flange tightly ceive a drain pipe threaded in from a second end 10 pressed against the shower pan. of said tubular portion opposite said first end, said 4. A shower and drain installation comprising: second thread being tapered so it is widest at the a preformed shower pan with upper and lower surend opposite the flange to form a water-tight enfaces and having a drain hole extending theregagement with the drain pipe, said first and second through between said upper and lower surfaces; threads being of the same handedness, whereby the a fitting having a tubular portion extending through drain pipe can be removed by turning it in the loossaid drain hole, said tubular portion having upper ening direction while holding the nut against turnand lower portions, said fitting also including a ing, all by a workman located under the shower flange at said upper tubular portion resting on the pan. upper surface portion of said pan which lies imme- 2. The drain fitting described in claim 1 wherein: diately about said drain hole, and said tubular porsaid fitting body has a third thread formed on the intion having first threads on the outside of its lower side of said tubular portion and tapered in a direcportion, second threads on the inside of its lower tion to receive a pipe threaded in from said first portion, and third threads on the inside of its upper end of said tubular portion, whereby a pipe reportion, at least said first and second threads being ceived in said third thread can be held to prevent right-handed; turning of the fitting during installation of a nut or a drain pipe with tapered threads threadably engaged drain pipe from below onto said first or second with said second threads and extending down- .threads. wardly therefrom; and 3. In a shower pan installation which includes a prea nut threadably engaged with said first threads and formed pan with a hole for closely receiving a drain fittightened to hold down said flange against the ting and a non-circular depression around said hole, the upper surface of said pan. combination with said pan comprising: 

1. A drain fitting for use on a preformed shower pan that has a drain hole of predetermined diameter comprising: a fitting body having a tubular portion for passage through said drain hole, a flange at a first end of said tubular portion for lying on the pan region surrounding said drain hole, a first thread formed on the outside of said tubular portion for threadably receiving a nut to hold said fitting body so the flange is held down tightly to the pan region surrounding the drain hole, and a seconD thread formed on the inside of said tubular portion to receive a drain pipe threaded in from a second end of said tubular portion opposite said first end, said second thread being tapered so it is widest at the end opposite the flange to form a water-tight engagement with the drain pipe, said first and second threads being of the same handedness, whereby the drain pipe can be removed by turning it in the loosening direction while holding the nut against turning, all by a workman located under the shower pan.
 2. The drain fitting described in claim 1 wherein: said fitting body has a third thread formed on the inside of said tubular portion and tapered in a direction to receive a pipe threaded in from said first end of said tubular portion, whereby a pipe received in said third thread can be held to prevent turning of the fitting during installation of a nut or drain pipe from below onto said first or second threads.
 3. In a shower pan installation which includes a preformed pan with a hole for closely receiving a drain fitting and a non-circular depression around said hole, the combination with said pan comprising: a fitting having a tubular portion for extending through said hole, said tubular portion having upper and lower end portions and having a non-circular flange received in said depression to prevent turning of said fitting, said tubular portion also having an external thread on its lower end portion; and a nut threadably engaged with said external thread and tightened thereon to hold the flange tightly pressed against the shower pan.
 4. A shower and drain installation comprising: a preformed shower pan with upper and lower surfaces and having a drain hole extending therethrough between said upper and lower surfaces; a fitting having a tubular portion extending through said drain hole, said tubular portion having upper and lower portions, said fitting also including a flange at said upper tubular portion resting on the upper surface portion of said pan which lies immediately about said drain hole, and said tubular portion having first threads on the outside of its lower portion, second threads on the inside of its lower portion, and third threads on the inside of its upper portion, at least said first and second threads being right-handed; a drain pipe with tapered threads threadably engaged with said second threads and extending downwardly therefrom; and a nut threadably engaged with said first threads and tightened to hold down said flange against the upper surface of said pan. 